import tkinter as tk
import random

def roll():
    lbl_result["text"]=str(random.randint(1,6))

window=tk.Tk()
window.title("")
window.columnconfigure(0, minsize=150)
window.rowconfigure([0,1], minsize=50)

btn_roll=tk.Button(master=window,text="Roll",fg="RED",bg="ORANGE",command=roll)
btn_roll.grid(row=0, column=0, sticky="nsew")

lbl_result=tk.Label(fg="GREEN",bg="BLACK")
lbl_result.grid(row=1, column=0, sticky="nsew")

window.mainloop()